1. Their Military is not enough to protect them
2. People had no respect for women and it started here, because they were out of work.
3. They were constantly distracted by warfare with northern tribes.
4. They fell because they were holding back the northern tribes.
5. the greatest weakness of the sung empire was holding back the northern tribes.
6. This was not a period of power or stability for china.
7. They also never managed to regain the land the Tang dynasty lost.